While attending the ATCS Monitor Day event at the Rochelle (IL) Railroad Park yesterday I realized that with the dozens of scanners that I have I didn't have even 1 portable with a discriminator tap!
Since I have a pair of Pro83's that serve me well and cost a mere pittance I decided to tap one of them and see how well it works. Being the sort of guy I am I decided to check if anyone else had already posted the info I needed to save the the work of actually finding the tap point and lo and behold the same guy that set up the ATCS Monitor event had posted the Pro-83 discriminator tap info to the Pro83 Yahoo group. To Gary, I say Thanks!
In looking at his method of routing the discriminator audio to the programming port I thought to myself "Self, do I really want to do that and lose the ability to program the radio via computer?" In reflection I thought not, and decided to take a different tack (or should it be tap?).
I looked in my junk drawers and found an audio cable/adapter that had a female stereo Mini jack brought out to 2 female phono jacks, one red and the other white. I cut off the mini jack and was left with a pair of phono jacks on about 4 inch cables.
After opening the case with the six screws (2 under the battery door, 4 directly on the back case) I found the LND-7 that Gary posted previously and tack soldered the center conductor from the phono jack lead. The shield was soldered to an existing metal plate soldered on the opposite side of the board. a small piece of electrical tape protected the board in case the shield gets pushed back towards it.
The Pro83 has 2 sets of black rubber grips on the sides of the radio. These turn out to be rubber shaped panels that can be pulled out after opening the case. I trimmed a bit off the right side one, right below the power jack and routed the phono jack cable thru this slot and reassembled the radio. The compression of the case being held together acts as a strain relief. I then removed the belt clip and routed the cable thru between the two screws from the top, with the jack itself protruding from the side of the radio behind the belt clip.
In testing the tap it seems to work great. I tried it in Trunker and with PL's and it decoded just fine. I did not use a tantalum capacitor since I have these in my various decoders already and I have never had a problem without one.
I will upload some photos soon to the PRO83 group.
Since I have a pair of Pro83's that serve me well and cost a mere pittance I decided to tap one of them and see how well it works. Being the sort of guy I am I decided to check if anyone else had already posted the info I needed to save the the work of actually finding the tap point and lo and behold the same guy that set up the ATCS Monitor event had posted the Pro-83 discriminator tap info to the Pro83 Yahoo group. To Gary, I say Thanks!
In looking at his method of routing the discriminator audio to the programming port I thought to myself "Self, do I really want to do that and lose the ability to program the radio via computer?" In reflection I thought not, and decided to take a different tack (or should it be tap?).
I looked in my junk drawers and found an audio cable/adapter that had a female stereo Mini jack brought out to 2 female phono jacks, one red and the other white. I cut off the mini jack and was left with a pair of phono jacks on about 4 inch cables.
After opening the case with the six screws (2 under the battery door, 4 directly on the back case) I found the LND-7 that Gary posted previously and tack soldered the center conductor from the phono jack lead. The shield was soldered to an existing metal plate soldered on the opposite side of the board. a small piece of electrical tape protected the board in case the shield gets pushed back towards it.
The Pro83 has 2 sets of black rubber grips on the sides of the radio. These turn out to be rubber shaped panels that can be pulled out after opening the case. I trimmed a bit off the right side one, right below the power jack and routed the phono jack cable thru this slot and reassembled the radio. The compression of the case being held together acts as a strain relief. I then removed the belt clip and routed the cable thru between the two screws from the top, with the jack itself protruding from the side of the radio behind the belt clip.
In testing the tap it seems to work great. I tried it in Trunker and with PL's and it decoded just fine. I did not use a tantalum capacitor since I have these in my various decoders already and I have never had a problem without one.
I will upload some photos soon to the PRO83 group.
